**My solutions to the problems found at Project Euler. **

```
# /usr/bin/python
# Problem: Sum the total of all primes below 2,000,000.
# Solution: I've done this before. Find all primes, add them. Hopefully my list isn't too big
# for memory, otherwise I might actually have to get creative (god forbid!)
#
# Note: I had a long debate with myself about this one. I decided to research quick prime-finding
# methods and came across a couple of sieve implementations. I've looked over the code for
# quite awhile and am pretty familiar with how it works, but I don't think I would have ever
# really come up with this on my own. I'm not a mathematician, and although I may be taking the
# easy way out, I don't have too many problems with using an existing algorithm. I've learned
# a couple of cool tricks from this code:
#
# I learned about:
# [] * n syntax
# xrange
# Extended slicing syntax.
#
# All in all, a victory. I will be using this algorithm in future solutions.
def primes(n):
""" Returns a list of primes < n """
sieve = [True] * n
for i in xrange(3,int(n**0.5)+1,2):
if sieve[i]:
sieve[i*i::2*i]=[False]*((n-i*i-1)/(2*i)+1)
return [2] + [i for i in xrange(3,n,2) if sieve[i]]
if __name__ == "__main__":
total = 0
for prime in primes(2000000):
total += prime
print total
```